Circuit controlling device



May 1, 1962 w. B. ELLWOOD CIRCUIT CONTROLLING DEVICE Filed June 25, 1959nws/vron By W. B. ELLWOOD A T TORNE V United States This inventionrelates to hermetically encapsulated circuit controlling devices,generally; and, in particular, to switching devices having operatingelements so arranged that adjustments may be made thereto after saidelements are mounted within an envelope in which they are to be sealed.

In many instances it is desirable to enclose a switching devicesoperating elements within an envelope for the purpose of avoidingcontamination of contact elements, fire hazard, etc. Although manyadvantages accrue from the use of hermetically encapsulated switchingdevices, many problems accompany the construction of such switchingdevices. Among these problems is the difficulty in achieving properadjustments of the operating elements within the envelope. Since inswitching devices of this type the envelope is ordinarily of glass andof relatively small bore, the difficulty of making and retaining properadjustments is obvious. Moreover, assuming that parts may be assembledwithin the envelope in proper adjust ment prior to sealing the envelope,there remains the hazard of maladjustment, particularly of metallicelements, due to the heat used in sealing the envelope.

Therefore, the objects of this invention are, among others, thefollowing: the improvement, structurally and functionally, of switchingdevices; the attainment of a switching device wherein the presetmensural and physical characteristics of its operating elements remainunchanged after the enclosure of those elements within a sealedenvelope; the attainment of a switching device wherein the presetmensural and physical characteristics of its operating elements areunaffected by the application of heat in the encapsulation of thoseelements within a sealed envelope; the attainment of a switching devicewherein operating elements, arranged within an envelope, are susceptibleof being finally adjusted just prior to sealing the envelope; and, theachievement of the aforementioned objects with simple, reliable andeconomical means.

The invention, hereinafter described in terms of a specific embodiment,achieves the aforementioned objects by the provision of a switchingdevice comprising: an envelope having an opening therein; operatingelements arranged within the envelope; and, adjustment means foradjusting the operating elements, the adjustment means being connectedwith at least one of the operating elements and extending without theenvelope, through the opening therein, whereby said elements aresusceptible of being finally adjusted prior to sealing the envelopesopening. In order to prevent thermally induced stresses from aifectingthe adjustments of the operating elements while the envelope is beingsealed, heat-flow retardation means are provided for limiting the amountof heat tha can be conducted to the operating elements.

Therefore, one of the features of this invention is the provision ofadjustment means, part of which are external to the circuit con-trollersenvelope, for performing final adjustments on the operating elements,situated within the envelope, prior to sealing the envelope. Anotherfeature of this invention is the provision of heat-flow retardationmeans for preventing maladjustments of the circuit controllers operatingelements as a result of sealing the operating elements within theenvelope by the application of heat thereto.

Other objects and features, as well as a fuller under- 3,032,628Fatented May 1, 1962 standing of the invention, will become apparent byreferring to the following description and claims, taken in conjunctionwith the accompanying drawings, in which:

FIG. 1 is a view, in longitudinal section, of a magnetically operableswitch in accordance with this invention;

FIG. 2 is a cross-sectional view of the switch, as taken along the line22, shown in FIG. 1;

FIG. 3 is another sectional view of the switch, as taken along the line3-3, as shown in FIG. 1; and

FIG. 4 is a sectional view of switch elements as in FIG. 1, partiallyassembled.

Referring now to the drawing, the magnetically operable switchingdevice, or, relay, there illustrated, is comprised of the switch unit,designated, generally, by the reference character 10, and the coil 12,encompassing the switch unit. As is shown at FIG. 1, the switch unit 10is comprised of: an envelope 11; the electrodes 14, 15 and 16, each ofwhich is sealed to, and protrudes through, the envelope; an armature 13mounted within the envelope; a spring member 17, connected with thearmature; and, a separator 19 for spreading the armature and the springmember apart from each other.

A convenient way of constructing the switch unit 10 is suggested at FIG.4. Two subassemblies, A and B, are illustrated there. Referring now toFIG. 4, the subassembly A is easily constructed by initially selecting aglass tube 11 having opposing open ends. The metallic electrodes 14 and15 are, then, sealed to the glass tube at one end thereof so that eachelectrode is disposed partly within, and partly without, the envelope.In the specific embodiment illustrated in the accompanying drawing, theelectrode 14 is a rod-like member of non-magnetizable material such asplatinum or the like; the electrode 15 is a bar-like member ofmagnetizable material such as No. 52 Alloy (52 percent nickel and 43percent iron) or the like.

In order to prepare the subassembly B, the reed-like armature 13 ofmagnetizable material is connected through a flexible hinge member 18 tothe end of the tubular electrode 16. The armature 13 has a free end 13aand a fixed end 13b; the armatures fixed end 13b being connected to thehinge member 18.

A spring member 17, having a free end 17a, is secured at its other end1712 to the fixed end 13b of the armature 13 by welding or anothersuitable process. A hairpinlike separator 19, having legs 19a and 19b,is positioned with its bight portion between the armature 13 and thespring 17.

As is illustrated at FIG. 4, the separators legs 19a and 19b extendthrough, and beyond, the opening in the electrode 16.

The armature 13, the hinge member 18 and the electrode 16 may befabricated from a material such as No. 52 Alloy or the like. The hingemember 18 has a thin cross-section to inhibit the conduction of heatfrom the electrode 16 to the armature 13 and to the spring memher 17.This heat is occasioned by the process of bonding the glass tube aboutthe outer periphery of the tubular electrode 16. As is illustrated inFIGS. 1, 2 and 3, one of the armatures longitudinal surfaces is curved.This curvature, as particularly illustrated in FIG. 2, is to provide alarge contact area between the armatures free end 1311 and the rod-likeelectrode 14 in order that a relatively low electrical resistance isachieved upon contact between the armature and the electrode.

The spring member 17 may be fabricated from a nonmagnetizable materialsuch as tungsten or the like. Although the spring member 17 is shown asa flexible rod in the accompanying drawing, it may be fashioned in otherforms. For example, it may be fashioned as a reedlike member. Theseparator 19 may be fabricated from 3 a material such as No. 52 Alloy,or brass, or the like. Although the separator 19 is shown inhairpin-like form in the accompanying drawing, it may be fashioned inother forms. For example, it may be fashioned into a shape resembling ahook.

Having prepared the sub-assemblies A and B, the subassembly B isinserted through the opening in the glass tube 11 of the sub-assembly A.Thereafter, the glass tube is bonded to the outer periphery of theelectrode 16. As is indicated hereinbefore, the hinge member 18, havinga thin cross-section, prevents the conduction of a great quantity of theapplied heat to the armature 13 and to the spring member 17.Beneficially, the resilience of the spring member 17, inter alia, is notchanged.

Having connected the sub-assemblies A and B in the manner hereinbeforedescribed, the separator 19 can be slidably positioned at a particularlocation, between the armature 13 and the spring member 17, bymanipulating the separators legs 19a. and 1% which protrude beyond theelectrode 16 as shown at FIG. 4. As the separator 19 is pulled towardthe armatures fixed end 13b, the armatures free end 13a is forcedagainst the electrode 14 and the spring members free end 17a. is forcedagainst the inner wall surface of the envelope 11. In order to establishthe proper armature and spring forces in relation to the ampere-turnsrequirements of the switch unit 10, the separator 19 is slidablyadjusted so that, at a predetermined magnitude of current through thecoil 12, the armatures free end 13a will break contact with theelectrode 14 and make contact with the electrode 15. When the locationof the separator 19 has been thus established, the end of the tubularelectrode 16 may be sealed as shown at FIGS. 1 and 3; the end of theelectrode being crimped and welded thereby sealing the envelope 11 and,as. a result, securing the separators legs 19a and 1912. Again, thehinge member 18 prevents a great quantity of the heat, generated duringthe welding process, from being conducted to the armature 13 and to thespring member 17. Therefore, the armature 13 and the spring member 17are not subject to maladjustments due to thermally induced stressresulting from the welding process. As an alternative, the electrode 16can be sealed by a cold-welding process.

The relay, as it is illustrated at FIG. 1 is in its unoperated, or,normal, status; i.e., in the absence of current flowing through thewindings of the. coil 12, the armatures free end 13a is in contact withthe electrode 14. When current of sufficient magnitude flows through thewindings of the coil 12, the relay assumes an operated status, i.e., thearmatures free end 13a breaks contact with the electrode 14 and makescontact with the electrode 15. Advantageously, the spring members freeend 17a, being in contact with the inner Wall surface of the envelope11, provides damping for the armature 13. Whenever the armatures freeend 13a moves from the electrode 14 to the electrode 15, or from theelectrode back to the electrode 14, the spring members free end 17aslides along the envelopes inner wall surface. The resulting frictionalforce inhibits the armatures tendency to bounce.

Although the invention has been illustrated and described in terms of aspecific embodiment, it is to be understood that the present disclosurehas been made by way of example only and that many changes in thedetails of construction and the combination and arrangements of partsmay be made without departing from the spirit and the scope of theinvention as it is hereinafter claimed.

What is claimed is: n

l. A circuit controlling device comprising an envelope having anaperture through a wall portion thereof, a first mounted on the firstelectrode, spring means within the envelope for biasing the armature toany one of a plurality of first positions, each of the first positionsbeing distant from the second electrode, adjustment means associatedwith the spring means for biasing the armature to a selected positionamong the first positions, part of said adjustment means being securedwithin the cavity to the first electrode, and magnetic means, outside ofthe envelope, operable for moving the armature from the selectedposition into contact with the second electrode.

2. A circuit controlling device comprising a non-magnetizable envelope,a non-magnetizable first electrode protruding through the envelope, amagnetizable second electrode protruding through the envelope, a thirdelectrode, including a cavity therein, protruding through the envelope,a magnetizable reed, including a fixed end and a free end, arrangedwithin the envelope, connection means for fastening the reeds fixed endto the third electrode, a leaf spring having a fixed end joined to thereeds fixed end and a free end extending toward the first and secondelectrodes, adjustable spacer means positioned between 'the reed and thespring for biasing the reeds free end against the first electrode andthe springs free end against the envelopes wall, said spacer meanshaving an extension portion disposed within the third electrodes cavityand secured thereat, and a coil, outside the envelope, operable formoving the reeds free end into contact with the second electrode.

3. A circuit controlling device as defined in claim 2 wherein theconnection means is a thin reed member having low thermal conductivity.

4. A circuit controlling device comprising an envelope having a ductprotruding through a portion thereof and defining an opening in theenvelopes wall, said duct being adaptable of being closed therebysealing the opening in the envelopes wall, actuating means situatedoutside the envelope, a movable member mounted within the envelope, saidmovable member being normally located at a first position and movabletherefrom, upon operation of the actuating means, to a second position,biasing means situated within the envelope for biasing the movablemember to the first position, and adjustment means for adjusting thebiasing means; part of said adjustment means extending outside theenvelope through the duct whereby the biasing means is capable of beingadjusted from outside the envelope prior to closing the duct therebysecuring the adjustment means.

5. A circuit controlling device comprising an envelope, a duct memberprotruding through the envelope and having an extending portion disposedoutside of the envelope, said'duct member including an aperturetherethrough defining a passage between, space inside the envelope andspace outside the envelope, the extending portion of said duct memberbeing adaptable of being deformed in order to seal the envelopes insidespace from the space outside the envelope, actuating means situatedoutside the envelope, a movable member mounted within the envelope, saidmovable member being normally situated at a first position and movabletherefrom, upon energization of the actuating means, to a secondposition, biasing means situated within the envelope for biasing themovable member to said first position, and adjustment means foradjusting the biasing means; part of said adjustment means extendingthrough said duct members aperture to the space outside the envelopewhereby said biasing means is finally adjusted from outside the envelopeprior to deforming said duct members extending portion thereby sealingthe envelope and securing the adjustment means.

6. A circuit controlling device comprising an envelope, first and secondelectrodes of non-magnetizable and magnetizable material, respectively,sealed'through a portion of the envelope, a third electrode, including acavity therein, sealed through another portion of the envelope, anarmature, within the envelope, having a hinge and secured to the thirdelectrode and a free end disposed between the first and secondelectrodes, an armature biasing spring having a hinge end thereofsecured to the armatures hinge end and a free end thereof extendingtoward the armatures free end, adjustable spacer means having a portionbetween the armature and the biasing spring for spreading them apart andanother portion extending into the third electrodes cavity and securedthereat, whereby said spacer means forces the armatures free end againstthe first electrode and forces the biasing springs free end against theenvelopes wall, and magnetic means outside of the envelope operable formoving the armatures free end into contact with the second electrode.

7. A circuit controlling device comprising an envelope having an innerwall surface, a magnetizable reed situated within the envelope, the reedhaving a fixed end and a free end, a reed-like spring member having afixed end and a free end, the reeds fixed end and the spring membersfixed end being joined together, mounting means for supporting the reedsfixed end, a separator located between the reed and the spring memberfor spreading the reeds free end apart from the spring members free end,the reeds free end being moved to a first position and the springmembers free end being moved into contact with the envelopes inner wallsurface, and magnetic means, outside of the envelope, operable formoving the reed to a second position.

8. A method of making a sealed circuit controller comprising the stepsof sealing two electrodes in parallel spaced relation through one end ofan envelope, securing one end of a magnetic armature to a tubularelectrode by means of a flexible hinge, bonding one end of an elongatedspring to the hinge end of the armature, placing a bight portion of anadjustment member between the armature and the spring with the remainderof the adjustment member extending through the tubular electrode,inserting the armature and the parts assembled thereto into the envelopeso that a portion of the armature is disposed between the twoelectrodes, bonding the envelope to the tubular electrode, placing theenvelope within the core area of a coil, energizing the coil whilepositioning the adjustment members bight portion to a position ofsatisfactory controller operation, and simultaneously sealing theenvelope and securing the adjustment member by sealing an end of thetubular electrode thereto.

9. A method of making a switching device comprising the steps ofassembling a magnetically movable member with a biasing means,adjustable for positioning the movable member at any of a plurality ofpositions, placing the movable member and part of the biasing meanswithin an envelope having an opening therein, adjusting the biasingmeans from outside the envelope to set the movable member at apredetermined position, sealing the envelopes opening thereby securingthe biasing means, and placing said envelope, movable member and biasingmeans within the influence of a magnetic field producing means.

10. A method of making a switching device comprising the steps ofplacing operating elements, including an adjustment member, within anenvelope having an opening in a wall portion thereof, said adjustmentmember extending without the envelope through said opening, manipulatingsaid adjustment member from without the envelope to adjust the operatingelements within said envelope, and sealing the opening in said envelopeswall portion thereby securing the adjustment member.

11. A method of making a switching device comprising the steps ofassembling a movable member with adjustment means for positioning themovable member, placing the movable member and part of the adjustmentmeans within an envelope having an opening therein, manipulating theadjustment means from without the envelope to set the movable member ata predetermined position, and sealing the envelopes opening therebysecuring the adjustment means.

12. A method of making a switching device comprising the steps ofassembling a non-magnetizable first electrode and a magnetizable secondelectrode within a nonmagnetizable envelope in spaced-apartrelationship, said first and second electrode protruding through a wallportion of the envelope, said envelope having an opening in another wallportion thereof, preparing a subassembly including a magnetizable reed,having a fixed end and a free end, a leaf spring, having a fixed end anda free end, a third electrode, having an aperture therethrough, and aspacer having a bight portion and an extension portion, said reeds fixedend being joined to the third electrode, said springs fixed end beingjoined to the reeds fixed end, said springs free end extending towardthe reeds free end, said spacers bight portion being situated betweenthe reed and the spring and said spacers extension portion passingthrough the third electrodes aperture, placing the subassembly into theenvelopes opening so that the reeds free end is disposed between thefirst and second electrodes, bonding the envelope about the thirdelectrode, manipulating the spacers extension portion from outside theenvelope to position the bight portion thereby forcing the reeds freeend against the first electrode and forcing the springs free end againstthe envelopes wall, and sealing the third electrode thereby securing thespacers extension portion.

13. The method of making a magnetically operable, spring biased, sealedswitch that comprises sealing a magnetizable electrode and anonmagnetizable electrode in parallel spaced relation through one end ofan insulating envelope, making a subassembly comprising a tube, amagnetizable armature, a flexible hinge, a spring and anadjusting-biasing member by securing the armature to one end of the tubeby means of the hinge, securing one end of the spring to the hinge endof the armature, wedging a bent-over end of the adjusting-biasing memberbetween the armature and the spring with an elongated portion of thismember extending through the tube, inserting the subassembly into theenvelope so that the free end of the armature is between the inner endsof the electrodes, sealing the tube to the envelope with a portion ofsaid tube extending therefrom, applying a magnetic field to themagnetizable elements, manipulating the adjusting-biasing member bymeans of its elongated portion to place the bent-over portion in aposition to properly bias the armature and spring for satisfactoryswitch operation, and closing the extending end of the tube on to saidelongated portion to secure the adjustingbiasing member and to seal theenvelope.

References Cited in the file of this patent UNITED STATES PATENTS2,406,021 Little Aug. 20, 1940 2,457,218 Ferrell Dec. 28, 1948 2,491,907Reifel et al Dec. 20, 1949 2,506,414 Ellwood May 2, 1950 2,527,475 BatesOct. 24, 1950 2,653,199 Brown et al. Sept. 22, 1953 2,921,161 Scata etal. Ian. 12, 1960

